Northwestern Crow (Corvus caurinus)

1999 ◽  
Author(s):  
N. A. Verbeek ◽  
Robert W. Butler
1999 ◽  
Author(s):  
N. A. Verbeek ◽  
Robert W. Butler

Ibis ◽  
2008 ◽  
Vol 123 (2) ◽  
pp. 183-189 ◽  
Author(s):  
Nicolaas A. M. Verbeek ◽  
Robert W. Butler

1991 ◽  
Vol 69 (6) ◽  
pp. 1534-1537 ◽  
Author(s):  
Nicolaas A. M. Verbeek

The number of natal down feathers (neossoptiles) and their arrangement in specific feather tracts of the body (pterylosis) are given for 19 nestlings of the northwestern crow, Corvus caurinus, from the Strait of Georgia, British Columbia. The natal pterylosis of the northwestern crow is compared with that of other members of the genus Corvus in the Nearctic and Palearctic regions. This comparison points out several differences in the capital, abdominal, and caudal tracts within the genus.


2020 ◽  
Author(s):  
N. A. Verbeek ◽  
Robert W. Butler

1985 ◽  
Vol 63 (4) ◽  
pp. 857-860 ◽  
Author(s):  
Paul C. James ◽  
Nicolaas A. M. Verbeek

An experimental study of clam storage by a Northwestern Crow (Corvus caurinus) was carried out on Mitlenatch Island, British Columbia, Canada. The crow was trained to take clams from a feeding table. His dispersion of the clams was studied using nearest-neighbour distance (NND). The distance clams were carried and the sequence of storage and recovery was also quantified. Median NND was significantly correlated with storage sequence position, as was NND with distance carried. The crow tended to recover the clams in the same order as he stored them, as storage sequence position was significantly correlated with recovery sequence position. The results were compared with other spatiotemporal studies of avian food hoarding. Recovery success of the crow was very high, he appeared to use memory to relocate his caches, as the majority of them were made in new sites, and he never revisited those already emptied.


1999 ◽  
Author(s):  
N. A. Verbeek ◽  
Robert W. Butler

1996 ◽  
Vol 6 (3) ◽  
pp. 261-269 ◽  
Author(s):  
Julia K. Parrish ◽  
Robert T. Paine

SummarySeabird populations suffer from a variety of natural and human-induced sources of mortality and loss of lifetime reproductive output. On the outer coast of Washington State, Common Murre Uria aalge populations have been in decline for approximately the last decade and are currently reproductively active only at Tatoosh Island. These murres nest in two basic habitat types: crevices (25% of the population) and larger cliff-top subcolonies (75%). Murres in cliff-top subcolonies have suffered dramatic reductions in reproductive success in recent years relative to conspecifics nesting in the crevices, primarily due to egg predation by Glaucous-winged Gulls Larus glaucescens and Northwestern Crows Corvus caurinus, facilitated by the presence of Bald Eagles Haliaeetus leucocephalus. Because predator removal is not feasible and creation of additional crevice habitat is difficult, expensive and potentially ineffective, we have designed a temporary habitat modification (the “silk forest”) which replaces the natural vegetation cover and modifies the interaction between murres and eagles. Within the test subcolony, murres nesting under and immediately adjacent to the silk forest produced nearly twice as many eggs per square metre as their conspecifics nesting in adjacent exposed-ground areas.


Sign in / Sign up

Export Citation Format

Share Document